introduce Cluster interface

pkg/cluster/cluster.go

@@ -178,7 +178,8 @@ func (c *Cluster) Create() error {
 	//TODO: service will create endpoint implicitly
 	ep, err := c.createEndpoint()
 	if err != nil {
-		return fmt.Errorf("could not create endpoint: %v", err)
+		c.Error = fmt.Errorf("could not create endpoint: %v", err)
+		return c.Error
 	}
 	c.logger.Infof("endpoint '%s' has been successfully created", util.NameFromMeta(ep.ObjectMeta))
 
@@ -188,41 +189,48 @@ func (c *Cluster) Create() error {
 		}
 		service, err := c.createService(role)
 		if err != nil {
-			return fmt.Errorf("could not create %s service: %v", role, err)
+			c.Error = fmt.Errorf("could not create %s service: %v", role, err)
+			return c.Error
 		}
 		c.logger.Infof("%s service '%s' has been successfully created", role, util.NameFromMeta(service.ObjectMeta))
 	}
 
 	if err = c.initUsers(); err != nil {
-		return err
+		c.Error = err
+		return c.Error
 	}
 	c.logger.Infof("User secrets have been initialized")
 
 	if err = c.applySecrets(); err != nil {
-		return fmt.Errorf("could not create secrets: %v", err)
+		c.Error = fmt.Errorf("could not create secrets: %v", err)
+		return c.Error
 	}
 	c.logger.Infof("secrets have been successfully created")
 
 	ss, err := c.createStatefulSet()
 	if err != nil {
-		return fmt.Errorf("could not create statefulset: %v", err)
+		c.Error = fmt.Errorf("could not create statefulset: %v", err)
+		return c.Error
 	}
 	c.logger.Infof("statefulset '%s' has been successfully created", util.NameFromMeta(ss.ObjectMeta))
 
 	c.logger.Info("Waiting for cluster being ready")
 
 	if err = c.waitStatefulsetPodsReady(); err != nil {
+		c.Error = err
 		c.logger.Errorf("Failed to create cluster: %s", err)
-		return err
+		return c.Error
 	}
 	c.logger.Infof("pods are ready")
 
 	if !(c.masterLess || c.databaseAccessDisabled()) {
 		if err := c.initDbConn(); err != nil {
-			return fmt.Errorf("could not init db connection: %v", err)
+			c.Error = fmt.Errorf("could not init db connection: %v", err)
+			return c.Error
 		}
 		if err = c.createUsers(); err != nil {
-			return fmt.Errorf("could not create users: %v", err)
+			c.Error = fmt.Errorf("could not create users: %v", err)
+			return c.Error
 		}
 		c.logger.Infof("Users have been successfully created")
 	} else {
@@ -495,6 +503,7 @@ func (c *Cluster) Update(newSpec *spec.Postgresql) error {
 	}
 
 	c.setStatus(spec.ClusterStatusRunning)
+	c.Error = nil
 
 	return nil
 }

pkg/cluster/sync.go

@@ -73,6 +73,8 @@ func (c *Cluster) Sync() error {
 		return fmt.Errorf("could not sync persistent volumes: %v", err)
 	}
 
+	c.Error = nil
+
 	return nil
 }
 

pkg/controller/controller.go

@@ -10,7 +10,6 @@ import (
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/cache"
 
-	"github.com/zalando-incubator/postgres-operator/pkg/cluster"
 	"github.com/zalando-incubator/postgres-operator/pkg/spec"
 	"github.com/zalando-incubator/postgres-operator/pkg/util/config"
 	"github.com/zalando-incubator/postgres-operator/pkg/util/constants"
@@ -31,7 +30,7 @@ type Controller struct {
 	logger   *logrus.Entry
 
 	clustersMu sync.RWMutex
-	clusters   map[spec.NamespacedName]*cluster.Cluster
+	clusters   map[spec.NamespacedName]spec.Cluster
 	stopChs    map[spec.NamespacedName]chan struct{}
 
 	postgresqlInformer cache.SharedIndexInformer
@@ -56,7 +55,7 @@ func New(controllerConfig *Config, operatorConfig *config.Config) *Controller {
 		Config:   *controllerConfig,
 		opConfig: operatorConfig,
 		logger:   logger.WithField("pkg", "controller"),
-		clusters: make(map[spec.NamespacedName]*cluster.Cluster),
+		clusters: make(map[spec.NamespacedName]spec.Cluster),
 		stopChs:  make(map[spec.NamespacedName]chan struct{}),
 		podCh:    make(chan spec.PodEvent),
 	}

pkg/controller/postgresql.go

@@ -134,9 +134,7 @@ func (c *Controller) processEvent(obj interface{}) error {
 		c.clustersMu.Unlock()
 
 		if err := cl.Create(); err != nil {
-			cl.Error = fmt.Errorf("could not create cluster: %v", err)
+			logger.Errorf("could not create cluster '%s': %v", clusterName, err)
-			logger.Errorf("%v", cl.Error)
-
 			return nil
 		}
 
@@ -149,17 +147,14 @@ func (c *Controller) processEvent(obj interface{}) error {
 			return nil
 		}
 		if err := cl.Update(event.NewSpec); err != nil {
-			cl.Error = fmt.Errorf("could not update cluster: %s", err)
+			logger.Errorf("could not update cluster '%s': %v", clusterName, err)
-			logger.Errorf("%v", cl.Error)
-
 			return nil
 		}
-		cl.Error = nil
 		logger.Infof("Cluster '%s' has been updated", clusterName)
 	case spec.EventDelete:
 		logger.Infof("Deletion of the '%s' cluster started", clusterName)
 		if !clusterFound {
-			logger.Errorf("Unknown cluster: %s", clusterName)
+			logger.Errorf("Cluster '%s' is not found", clusterName)
 			return nil
 		}
 
@@ -191,11 +186,9 @@ func (c *Controller) processEvent(obj interface{}) error {
 		}
 
 		if err := cl.Sync(); err != nil {
-			cl.Error = fmt.Errorf("could not sync cluster '%s': %v", clusterName, err)
+			logger.Errorf("%v", "could not sync cluster '%s': %v", clusterName, err)
-			logger.Errorf("%v", cl.Error)
 			return nil
 		}
-		cl.Error = nil
 
 		logger.Infof("Cluster '%s' has been synced", clusterName)
 	}

pkg/spec/types.go

@@ -1,9 +1,9 @@
 package spec
 
 import (
+	"database/sql"
 	"fmt"
 	"strings"
-	"database/sql"
 
 	"k8s.io/client-go/pkg/api/v1"
 	"k8s.io/client-go/pkg/types"
@@ -73,6 +73,28 @@ type UserSyncer interface {
 	ExecuteSyncRequests(req []PgSyncUserRequest, db *sql.DB) error
 }
 
+type ClusterEventHandler interface {
+	Create() error
+	Update(*Postgresql) error
+	Delete() error
+	Sync() error
+}
+
+type ClusterCommandExecutor interface {
+	ExecCommand(*NamespacedName, ...string) (string, error)
+}
+
+type ClusterController interface {
+	Run(<-chan struct{})
+	ReceivePodEvent(PodEvent)
+}
+
+type Cluster interface {
+	ClusterEventHandler
+	ClusterCommandExecutor
+	ClusterController
+}
+
 func (n NamespacedName) String() string {
 	return types.NamespacedName(n).String()
 }